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When to Plant Geraniums in Washington County, VT

Geraniums (Pelargonium × hortorum) are tender perennials grown as warm-season annuals throughout North America. Prized for their bold flower clusters, long bloom period, and tolerance of summer heat when planted in well-drained soil, they anchor window boxes, containers, and bed borders from late spring until hard frost. Zones 9b–11b can overwinter plants in the ground.

Washington County, Vermont is in USDA Zone 5a. The average last spring frost is May 12 and the first fall frost is October 7, giving you a growing season of approximately 148 days.

At an elevation of 959 feet, Washington County receives approximately 41.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Geraniums to ensure they mature before fall.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Washington County, VT (Zone 5a) Short season
148 days
Last Spring Frost May 12
148 growing days
First Fall Frost October 7

Washington County Soil Profile

Soil Type

Silt Loam

Soil pH

5.1-6.3

Drainage

Well Drained

Monthly Watering Guide for Geraniums

Geraniums needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Geraniums Needs Rainfall You Supplement Action
Jan 3.1" 0" ❄️ Dormant
Feb 2.8" 0" ❄️ Dormant
Mar 3.4" 0" ❄️ Dormant
Apr 3.5" 0" ❄️ Dormant
May 4.3" 4.1" 0.2" 💧 Light watering
Jun 4.3" 4.2" 0.1" 💧 Light watering
Jul 4.3" 4.1" 0.2" 💧 Light watering
Aug 4.3" 3.4" 0.9" 💧 Light watering
Sep 4.3" 3.2" 1.1" 💧 Light watering
Oct 4.3" 3.5" 0.8" 💧 Light watering
Nov 2.8" 0" ❄️ Dormant
Dec 3.4" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Washington County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Geraniums Planting Timeline — Washington County, VT

Geraniums Planting Calendar

Activity When Date Range
Start Indoors March 3 Mar 3 – Mar 17
Transplant Outdoors May 19 May 19 – Jun 2
Bloom July 28 Jul 28 – Oct 20

Plant 0.1" deep · 12" apart · Rows 14" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April
May Transplant Outdoors
June Transplant Outdoors
July Bloom
August Bloom
September Bloom
October Bloom
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

148 days in Washington County

Growing Tips for Washington County

Start seeds indoors 10–12 weeks before last frost — germination is slow and erratic without bottom heat (70–75°F). Transplant after frost danger passes. Geraniums rarely direct-sown; cuttings or transplants are the standard. Deadhead spent umbels weekly to maintain continuous bloom. Let soil dry slightly between waterings to prevent root rot. In zones 10–11 plants may be left in ground year-round or overwintered as houseplants.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Geraniums in Washington County, VT?

Washington County is in Zone 5a with an average last frost of May 12. Plan your Geraniums planting based on this frost date — see the calendar above for exact timing.

What planting zone is Washington County, VT?

Washington County, Vermont is in USDA Hardiness Zone 5a. The average last spring frost is May 12 and first fall frost is October 7.

🌱

Your Washington County Garden Planner — Free

A 22-page printable planner built for Washington County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Washington County, VT. Local conditions may vary. Last updated: July 2026.

Sources & credits

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